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1.
AOT—正庚烷微乳状液的制备及迁移痕量金属离子的研究   总被引:1,自引:0,他引:1  
研究了以二-(2-乙基己基)磺化琥珀酸黄为表面活性剂,以正庚烷为油性溶剂的W/O型微乳状液的形成及迁移痕量金属离子的行为,确定了制乳和迁移的适宜条件,在此条件下,一些金属离子可较完全地水相或料相迁移到微乳相中,显示出较高的迁移率。  相似文献   

2.
适用于痕量金属离子迁移的微乳状液的制备及其迁移条件   总被引:6,自引:1,他引:6  
韩立新  李克安 《分析化学》1997,25(3):280-282
研究了以气溶胶OT为表面活性剂与不同烃类的油性溶剂及不同醇类的助表面活性剂一起制备的油包水型微乳为Cd62+从水相或料相迁移到微乳中的影响,同时还观察了油水比和温度对金属离子迁移的影响,从而确定了适于痕量金属离子迁移的微乳体系和和Cd^2+为规范离子的迁移条件。  相似文献   

3.
研究了一些流动载体对以二-(2-乙基己基)磺化琥珀酸钠(AOT)为表面活性剂、正庚 烷为油性溶剂的W/O型微乳状液在迁移痕量金属离子Cu2+的影响。实验结果表明,1-(2-吡 啶偶氮)-2萘酚(PAN)能大大促进 Cu2+的迁移,使其迁移率从 70%上升到 100%。用高盐度 溶液对微乳进行破乳,得到 Cu2+的富集倍数为 6,回收率约为 100%。  相似文献   

4.
韩立新  李克安 《分析化学》1998,26(7):880-882
研究了一些流动载体对以二-(2-乙基己基)磺化琥珀酸钠(AOT)为表面活性剂,正庚烷为油性溶剂W/O型微乳状液在迁移痕量金属离子Cu^2+的影响,实验结果表明,1-(2-吡啶偶氮)-2-萘酚(PAN)能大大促进Cu^2+的迁移,使其迁移率从70%上升到100%,用高盐度溶液对微乳进行了破乳,得到Cu^2+的富集倍数为6,回收率约为100%。  相似文献   

5.
微乳凝胶中小分子传质研究   总被引:1,自引:0,他引:1  
微乳凝胶中小分子传质研究对于拓宽胶束酶学研究内涵、加速酶在生物合成与转化领域中的应用、研制高性能生物传感器等具有重要理论意义和潜在应用价值.以微乳液中二价金属离子与紫脲酸胺之间的配位反应为指示反应,采用分光光度技术,研究了金属离子在由阳离子表面活性剂十六烷基三甲基溴化胺构建的微乳凝胶中的传质问题.结果表明,在由含紫脲酸胺微乳液及含金属离子微乳凝胶构成的体系中,金属离子在微乳凝胶中的传质是金属离子与紫脲酸胺配位反应的限速步骤.为进一步证实上述结论,还对影响金属离子在微乳凝胶中传质的各种因素(如微乳液中水与表面活性剂的摩尔比值、分散相中甘油与水的配比等)进行了研究,结果也证实了上述结论.  相似文献   

6.
邹长英  李克安 《分析化学》1994,22(11):1151-1154
用双(2,4,4-三甲基戊基)膦酸-Span80-甲苯乳状液膜体系研究了汞的迁移行为,确定了用此种乳状液膜迁移分离汞的适宜条件,汞在5min内可迁移96%以上。在同样条件下,一些常见过渡金属离子如Co^2+,Ni^2+,Cu^2+,Cd^2+等通过此乳状液膜的迁移率很低,因此汞可与这些元素得到很好的分离。  相似文献   

7.
用Cyanex272-Span80-甲苯乳状液膜研究了Zn^2+的迁移行为,在适宜条件下,5min内锌的迁移率达95%以上,而在此条件下,与锌性质相近的镉、铜、钴、镍、汞等金属离子不迁移或迁移率很低。因此,用此乳状液膜体系可将锌与镉及其它常见离子分离。  相似文献   

8.
研究了微乳毛细管电动色谱体系中,表面活性剂、助表面活性剂、微乳液的内相、有机改性剂等微乳组成对分析窗口的影响.以甲醇为电渗流标记物测定电渗流时间,以强疏水性化合物菲为标记物测定微乳液滴(假固定相)的迁移时间,分析时间窗口的变化.最佳条件下,菲的迁移时间和峰面积的相对标准偏差小于1.6%和3.0%(n=6),体系稳定,重复性良好.根据时间窗口的变化规律对其进行适当调节,成功实现了5种水溶性和2种脂溶性维生素的分离,并与毛细管区带电泳及胶束毛细管电动色谱进行了比较.  相似文献   

9.
用三正辛胺-SPAN80-二甲苯乳状液膜体系迁移Mo( Ⅵ)的研究表明,在合适的制乳和迁移条件下,Mo( Ⅵ)可以快速,完全地迁入内相,并能与Fe^2 ,Cu^2 ,Co^2 ,Ni^2 ,Zn^2 ,Cd^2 ,Mn^2 等常见离子分离。  相似文献   

10.
研究了以OP(辛基酚聚氧乙烯醚)为表面活性剂、正己醇为助表面活性剂、磺化煤油为溶剂的W/O型微乳状液的形成及对盐酸介质中钛的萃取,确定了制乳、萃取和破乳的适宜条件。在此条件下,盐酸介质中的钛可较完全地从水相迁移到微乳相中,经升温破乳又从有机相中释放出来。通过微乳萃取过程,可实现盐酸介质中钛的分离和富集。  相似文献   

11.
A method is proposed and explored for speciation of Cr(III) and Cr(VI), selective extraction and preconcentration in various water samples based on dynamic and static techniques. Three newly designed alumina phases-physically adsorbed-2-pyridenecarboxyladehyde-thiosemicarbazone [Al-2PC-TSC (I–III)] were synthesised and characterised. Stability tests and application of [Al-2PC-TSC (I–III)] as inorganic ion exchangers and chelating solid sorbents for various metal ions were studied and evaluated. The distribution coefficient and separation factors of chromium species versus other interfering metal ions were determined to examine the incorporated selectivity into these alumina phases. Quantitative recovery of Cr(VI) was accomplished by [Al-2PC-TSC (I–III)] at pH = 1.0 while Cr(III) was found to be quantitatively recovered on these sorbents at pH = 7.0 with minimal or no interference between these two species under the studied buffering conditions. Selective solid phase speciation and preconcentration of Cr(III) and Cr(VI) in various real water samples were successfully performed and accomplished via a micro-column, with 200 as a preconcentration factor. Selective speciation of Cr(VI) and Cr(III) via preconcentration from seawater and industrial water samples by alumina phases in pH = 1 was found to give percentage recovery values of Cr(VI) in the range 93.5–97.3 ± 3.0–5.0% and 94.0–97.5 ± 3.0–4.0%, for seawater and industrial water samples, respectively.  相似文献   

12.
W/O型微乳状液迁移和富集痕量金属离子Cd2+、Cr3+的研究   总被引:12,自引:0,他引:12  
利用各种分离技术分离和富集金属离子,无论是在环境保护还是在湿法冶金方面都具有重要的意义.油包水型微乳状液因具有独特的物理化学性质,已越来越广泛地应用于金属离子的萃取分离上.  相似文献   

13.
A novel flow injection chemiluminescence (CL) method has been developed for the determination of three metal ions, namely Fe2+, Fe3+ and Cr3+, based on the second CL (SCL) signal of the mixture of luminal with KMnO4 in a sodium hydroxide medium by the catalysis of Fe2+, Fe3+ or Cr3+. The possible CL mechanism of the systems, the influencing factors, and the optimum conditions for the reactions were investigated based upon the kinetic curve of the CL reaction, CL spectra, UV-visible spectra and some other experiments. Under the optimum conditions, the SCL intensity was directly proportional to the concentration of these metal ions in solution in the range of 0.10 - 100.00 mg l(-1) for Fe(2+), 0.50 - 7.50 and 7.50 - 200.00 mg l(-1) for Fe3+, 0.01 - 0.25 and 0.25 - 10.00 mg l(-1) for Cr3+. The detection limits (3 sigma/s) were 9.87 x 10(-6) g l(-1), 2.71 x 10(-6) g l(-1) and 5.25 x 10(-7) g l(-1) for Fe2+, Fe3+ and Cr3+, respectively.  相似文献   

14.
The construction and performance characteristics of a novel chromate ion-selective membrane sensor are described and used for determining chromium(III) and chromium(VI) ions. The sensor is based on the use of a rhodamine-B chromate ion-associate complex as an electroactive material in a poly(vinyl chloride) membrane plasticized with o-nitrophenyloctyl ether as a solvent mediator. In a phosphate buffer solution of pH 6 - 7, the sensor displays a stable, reproducible and linear potential response over the concentration range of 1 x 10(-1) - 5 x 10(-6) mol l(-1) with an anionic Nernstian slope of 30.8 +/- 0.5 mV decade(-1) and a detection limit of 1 x 10(-6) mol l(-1) Cr(VI). High selectivity for Cr(VI) is offered over many common anions (e.g., I-, Br-, Cl-, IO4-, CN-, acetate, oxalate, citrate, sulfate, phosphate, thiosulfate, selenite, nitrate) and cations (e.g., Ag+, Ca2+, Sr2+, Co2+, Ni2+, Cu2+, Mn2+, Fe2+, Zn2+, Cd2+, Al3+, Cr3+). The sensor is used for determining Cr(VI) and/or Cr(III) ions in separate or mixed solutions after the oxidation of Cr(III) into Cr(VI) with H2O2. As low as 0.2 microg ml(-1) of chromium is determined with a precision of +/-1.2%. The chromium contents of some wastewater samples were accurately assessed, and the results agreed fairly well with data obtained by atomic absorption spectrometry.  相似文献   

15.
Oligopeptide lactones (theonellapeptolides) isolated from the Okinawan marine sponge Theonella swinhoei and resin-glycosides (merremosides) from the tuber of an Indonesian medicinal plant Merremia mammosa were examined regarding their activities in transporting Na+, K+, and Ca++ ions into human erythrocytes. Each of these lactones, which had been shown, using a supported liquid membrane, to have an ionophoretic effect on the alkali metal ions, transported the ions to a different extent. The ion transporting activities of these compounds were completely lost when the macrocyclic lactone structures were cleaved by sodium methylate. Resin-glycosides with an additional branched glycosyl residue showed much greater ion transporting activities than those without it.  相似文献   

16.
非水反相微乳的加溶与电导性质研究   总被引:7,自引:0,他引:7  
研究了若干非水极性溶剂(甲酰胺、二甲基亚砜和乙腈)及其与水的混合物/AOT/正庚烷反相微乳体系的加溶性质及其电导行为.结果表明,在AOT反相微乳中,非水极性溶剂的最大加溶量均远小于水的加溶量.其最大加溶量顺序为二甲基亚砜< 甲酰胺< 乙腈< 水.甲酰胺和乙腈与水的加溶相互抵制,而水在一定范围内可促进二甲基亚砜的加溶.非水反相微乳的电导率随加溶量的变化规律与含水反相微乳体系类同,但到达电导率极大值和出现渗滤时的加溶量明显比含水反相微乳 体系的要小.  相似文献   

17.
This study describes the use of banana peel, a commonly produced fruit waste, for the removal of Cr(VI) from industrial wastewater. The parameters pH, contact time, initial metal ion concentration, and temperature were investigated and the conditions resulting in rapid and efficient adsorption (95% within 10 min) were determined. The binding of metal ions was found to be pH dependent with the optimal sorption occurring at pH 2. The retained species were eluted with 5 mL of 2 M H2SO4. To elucidate the mechanism of the process, total amounts of chromium and Cr(VI) were analyzed using flame atomic absorption and ultraviolet–visible (UV–vis) spectroscopic techniques, respectively. The Langmuir and Dubinin–Radushkevich (D–R) isotherms were used to describe the partitioning behavior for the system at different temperatures. Kinetics and thermodynamics of Cr(VI) removal by banana peel were also studied. The influence of diverse ions on the sorption behavior revealed that only Fe(II) ions (of those tested) suppressed the sorption of Cr(VI) ions to some extent. The method was applied for the removal of Cr(VI) from industrial wastewater.  相似文献   

18.
研究了硫酸铵-溴化钾铵-正丙醇体系萃取分离和富集锗的行为及与一些金属离子分离的条件.硫酸铵能使正丙醇的水溶液分成两相,在分相过程中,Ge4+与KBr生成(GeBr62-),并与质子化正丙醇(C3H7OH2+)形成缔合物[GeBr62-][C3H7OH2+]2,此缔合物能被正丙醇相完全萃取.当正丙醇、KBr和硫酸铵的浓度分别为30%(V/V)、7.0×10-3mol/L、0.20g/mL时,(GeBr62-)的萃取率达到97.7%以上,而Ni2,Pb2,Cr3+,Co2,Fe3+,Al3+,Mg2+,Ag+,Bi3+,CH2,W(Ⅵ)和V(Ⅴ)基本不被萃取,实现了Ge4+与上述金属离子的分离.  相似文献   

19.
An electrolyte system, using malic acid as a complexing agent, has been developed to allow the determination of transition metal cations using miniaturised isotachophoresis. The method allowed the simultaneous determination of Mn2+, Cr3+, Fe2+, Co2+, Zn2+ and Ni2+ to be made without interference from other common ions. Limits of detection were calculated to be in the range 0.5-1.0mg l(-1) for Mn2+, Cr3+ Co2+ and Zn2+ and 2.0 mg l(-1) for Fe2+ and 4.7 mg l(-1) for Ni2+. The successful analysis of five industrial samples, containing a range of these metal ions, obtained from metal processing plants were achieved in under 13 min. The separations were performed on a poly(methyl methacrylate) chip with integrated platinum wire conductivity detection electrodes.  相似文献   

20.
In acidic medium and in the presence of chloride ions 2-[2-(4-methoxy-phenylamino)-vinyl]-1,3,3-trimethyl-3H-indolium chloride forms complex with Cr(VI). The optimum conditions (pH, concentration of Cl- and the complex forming reagent) of the separation and extraction of Cr(VI) into toluene using this basic dye as a complexing reagent have been determined and the possible interferences of Ca, Mg, Na, K, Cr(III), Ni, Pb, Hg, Mn, Al, Cu have been studied. An electrothermal atomic absorption spectrometer (GFAAS) was used for the determination of Cr(VI). The detection limit of the method for Cr(VI) found to be 0.15 μg dm− 3 and RSD for spiked drinking water was better than 3%.  相似文献   

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